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1164 Chapter 14: character studio
3.
In the Path Follow Behavior rollout, click
the None button and pick the shape for the
delegates to follow.
4. Set the Radius parameter to the number of
units by which delegates can str ay from t he
path. Change other settings as desired.
TousetheSurfaceArrivebehavior:
1.
Add a Surface Arrive behavior to the Crowd
object.
2. Add an object or objects to serve as the target
surface to the scene.
Note: If you use multiple objects, delegates will
arriveatthesurfaceoftheclosestobject.
3. In the Surface Arrive Behavior rollout,
clickNoneorMultipleSelectiontodesignate
the one or more target objects.
4. Use the settings in the Location group to
determinewherethedelegatewillstopwhenit
reaches a target object.
5. Use the settings in the Approach group to
determinehowthedelegatewillbehavewhenit
approaches the target.
To use the S ur face Follow behavior:
1.
Add a Surface Follow behavior to the Crowd
object.
2. Add an object or objects to serve as the follow
surface to the scene.
Note: If you use multiple objects, they must
intersect to form a contiguous surface. Each
delegate wil l move to the closest surface, follow
it to the next closest that it encounters, and then
start following that one, and so on.
3. In the Surface Follow Behavior rollout,
clickNoneorMultipleSelectiontodesignate
the object or objects w hose surface(s) the
assignees are to follow.
4. If you like, use t he settings in the Projection
Vector group to force delegates to move in a
specific direction.
Obsta cl e Avoida nce
An important part of crowd behavior is avoidance
of obstacles. Think of an obstacle as any thing that
impedes a crowd m ember’s progress. Examples
of obstacles include walls, telephone poles,
and fences, as well as other crowd members.
Encountering such objects can ca use avoidance
behavior , which consists of an y combination of
slowing down, turning, and stopping.
There are several ways to implement avoidance in
character studio,including:
•TheAvoid behavior (page 2–1211) is one of
the most commonly used behaviors. Use this
behavior to cause crowd members to avoid
other crowd members, or spherical objects
in the scene. It works by creating a spherical
volume of avoidance around the avoided object,
so it doesn’t accommo date irregular objects.
The Avoid behavior is unl ike any other behavior
in C rowd. After all the other behav iors exert
their forces on the delegates, Avoid tak es over
and has the power to turn, slow down, and
even stop a delegate in order to ma ke it avoid
an obstacle.
•UsetheWall Repel behavior (page 2–1227)
to cause crowd members to avoid broad, flat
objectssuchaswallsandfences.Youcanset
a maximum distance for the repel effect, and
describetherateatwhichtheforceawayfrom
the wall increases as a delegate approaches the
wall.
Unlike the Avoid behavior, which can stop
or slow dow n a delegate, Wall Repel simply
exerts a force on the delegate to turn it away
from the wall. It does not g uarantee wall
avoidance. You must work with it’s distance